Service Domain Routers (SDRs) are a type of computer network device configuration where a physical router can be partitioned into several independent routers that are independently managed. This model can also be used to collapse multiple SDRs (routers), possibly across multiple devices, into one physical system. Routing and forwarding adjacencies can be set up between these SDRs. Generally, customers do not like using available ports to establish these SDR adjacencies, particularly since for some customers the adjacency would use ports that could otherwise be for generating revenue.